DTC P0A78-266: Drive Motor "A" Inverter Performance; DTC P0A78-267: Drive Motor "A" Inverter Performance: Description

The inverter contains a three-phase bridge circuit, which consists of six power transistors (IGBTs) each for MG1 and MG2. The inverter converts high-voltage direct current from the HV battery into three-phase alternating current for MG1 and MG2; it also converts three-phase alternating current supplied by MG1 and MG2 into direct current for the HV battery. The MG ECU controls the actuation of the power transistors (IGBTs). The inverter transmits information necessary for control, such as amperage and voltage, to the MG ECU.

Fig 1: MG1 & MG2 High Voltage Converter Diagram

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The MG ECU uses a voltage sensor, which is built into the inverter, to detect boosted high voltage (VH) to allow control of the voltage boost.

The inverter voltage sensor outputs voltage that varies between 0 and 5 V in accordance with the changes in the boosted voltage. The higher the boosted voltage, the higher the sensor output voltage, and the lower the boosted voltage, the lower the sensor output voltage.

The MG ECU monitors the inverter voltage and detects malfunctions.